Studies Find Stronger Benefits Of Breast Milk

July 21, 1996|By Laura Beil, Dallas Morning News.

Pediatricians know that the best formula for a baby is mother's milk. But new studies suggest that breast milk is not only better, but almost twice as good as formula at protecting babies from infections.

In fact, research this decade has been so convincing that the American Academy of Pediatrics is expected to release a policy statement this summer stressing that breast-feeding should be the first option for newborns, and not the alternative.

"This is the strongest thing I've ever seen come out of the academy," said Dr. Marianne Neifert, a Denver pediatrician and member of the committee drafting the academy's stance.

"It has a lot of very strong statements in it," Neifert said. For example, she said, instead of stating something like, "Formula is the closest thing to breast milk," the new policy will say, "Formula is a distant second."

The doctors are motivated by the fact that newer research does not have the complications that plagued earlier work.

In the underdeveloped nations of Africa and Asia, studies have drawn clear conclusions about the benefits of breast milk partly because living conditions are more uniform and formula-feeding can actually be dangerous. In poorer countries, a mother may improperly dilute the formula because the directions are not clear, or she may contaminate it because safe drinking water is not available.

But in developed countries, formula-feeding is by no means hazardous, and the differences between the two methods are harder to tease apart. For instance, the decision to breast-feed may reflect something about a mother's education and economic status, and those influences may actually be keeping a baby healthier, not the breast milk. Or, working mothers may find it more difficult to breast-feed, and therefore use formula. But their babies may get more infections not because of the formula, but because they may be more likely to spend time in day-care centers.

"You can't entirely separate breast-feeding from the family and society from which the child comes," said Dr. Lawrence Gartner of the University of Chicago, chairman of the American Academy of Pediatrics' Work Group on Breast Feeding.

Then there's the definition of breast-feeding. Some studies have counted babies as breast-fed if they got any breast milk at all, Neifert said.

All of which has made the issue extremely difficult to examine. This year, however, scientists from the U.S. Centers for Disease Control and Prevention and the Food and Drug Administration have conducted a study that tries to take all of this into consideration. More than 1,000 mothers filled out monthly questionnaires after their babies were born. The survey asked how frequently the babies were breast-fed and the incidence of diarrhea and ear infections that month. It also asked about the parents' income, household size, smoking habits and other circumstances known to affect the rate of infections.

The study also accounted for a phenomenon called "reverse causality," which happens when a disease has an effect on behavior, and not vice versa. In this case, the researchers wanted to be certain that a mother didn't change feeding patterns because the baby got diarrhea.